1. Field of the Invention
This invention relates to a concrete pump apparatus and more particularly to a telescopic boom-mounted concrete pump apparatus.
2. Description of the Related Art
Concrete is sometimes pumped to locations where it is difficult or impossible for a concrete mixer truck to gain access thereto. Such is the case where concrete is to be poured behind a house or the like where it is impossible to drive the concrete mixer truck. One alternative to such a situation is to use wheelbarrows to transport the concrete to the location where it is to be placed. Another solution has been to utilize a telescoping or articulated boom assembly which is mounted on a truck. In some cases, a concrete pump is positioned on the truck and a concrete conduit, such as a flexible hose, is extended from the pump, along the length of the telescoping boom, at the exterior surface thereof, to a discharge conduit from which the concrete is discharged. The telescoping boom is extended and maneuvered to position the discharge conduit at the proper location.
The assignee of the present invention is the owner of U.S. Pat. No. 6,142,180 entitled A CRANE-MOUNTED CONCRETE PUMP APPARATUS as well as U.S. Pat. No. 6,220,292 entitled A CRANE-MOUNTED CONCRETE PUMP APPARATUS. In U.S. Pat. No. 6,142,180, a flexible hose extends between the discharge side of the concrete pump and the rearward end of the concrete conduit positioned within the telescopic boom assembly. The flexible hose is coiled on the crane platform when not in use. As the telescopic boom is extended, the flexible hose is pulled from the coil of the interior of the boom assembly. When the boom assembly is retracted, it is necessary to pull the hose rearwardly from the interior of the boom assembly and position the same on the crane platform. In U.S. Pat. No. 6,220,292, the flexible hose connecting the concrete pump with the concrete conduit within the boom assembly is wound upon a powered hose reel, rotatably mounted on the rearward end of the boom assembly. Although both of the above-identified patents represent a significant advance in the art, the instant invention eliminates the need for coiling the flexible hose on the crane platform and eliminates the need for a powered hose reel. In addition, the instant invention is more maneuverable than the devices of the above-identified patents.
A telescopic boom-mounted concrete pump apparatus is provided with the apparatus being mounted on a truck having a rotatable pedestal assembly mounted thereon rearwardly of the cab of the truck. A telescoping boom assembly is pivotally secured to the pedestal and extends outwardly and normally upwardly therefrom. A hydraulic cylinder pivotally connects the telescoping boom assembly to the pedestal for pivotally moving the telescoping boom assembly with respect to the pedestal. The telescoping boom assembly preferably comprises an inner boom member, an intermediate boom member slidably mounted in the interior of the inner boom member, and an outer boom member slidably mounted in the interior of the intermediate boom member. For purposes of description, the inner boom member will be described as having inner and outer ends and first and second sides while the intermediate and outer boom members will be described as having inner and outer ends. The outer boom member is movable with the intermediate boom member as the intermediate boom member is retracted and extended. A first concrete conduit, having inner and outer ends, is positioned at the outer side of the inner boom member with the inner end of the first concrete conduit being positioned at the inner end of the inner boom member. The outer end of the first concrete conduit is positioned at the outer end of the inner boom member. The inner end of the first concrete conduit is in communication with a source of concrete under pressure. One end of a flexible concrete hose is operatively connected to the outer end of the first concrete conduit. A first elongated support is mounted on the inner boom member at the first side thereof. A second elongated support is mounted on the inner boom member at the second side thereof. A third elongated support is movably mounted on the second elongated support and is movable between retracted and extended positions with respect to the second elongated support. The outer end of the third elongated support is secured to the intermediate boom member so that the third elongated support moves from its retracted position to its extended position as the intermediate boom member is moved from its retracted position to its extended position. The inner end of a second concrete conduit is in fluid communication with the second end of the flexible concrete hose with the outer end of the second concrete conduit being secured to the outer end of the outer boom member for movement therewith. The second concrete conduit is positioned on the third elongated support when the outer boom member is in its retracted position. The second concrete conduit extends from the outer end of the third elongated support when the outer boom member is in its extended position. The flexible concrete hose is positioned on the first elongated support and at least partially positioned upon the second elongated support when the intermediate and outer boom members are in their retracted positions. A concrete discharge conduit in the form of a rigid jib boom member is pivotally and rotatably secured to the outer end of the outer boom member and includes a self-aligning mechanism which normally maintains the rigid jib boom member in a pivotal aligned relationship with respect to the truck. A flexible concrete discharge hose is secured to the outer end of the rigid jib boom member. The construction of the apparatus of this invention enables the boom assembly to be moved into low buildings with the jib boom member being able to pivot around pillars, columns or the like. Further, the arrangement of the various components allows concrete to be discharged at a location close to the truck.
It is therefore a principal object of the invention to provide an improved concrete pumping apparatus.
A further object of the invention is to provide a telescopic boom-mounted concrete pump apparatus.
Still another object of the invention is to provide a telescopic boom-mounted concrete pump apparatus wherein the telescopic boom may be extended into low buildings.
Yet another object of the invention is to provide an apparatus of the type described which includes a pivotal jib boom member which may be pivoted around obstructions within the building.
These and other objects will be apparent to those skilled in the art.